Add script to write the serial print into a log file.

scripts/log-serial/log-serial.py

@@ -0,0 +1,37 @@
+#!/usr/bin/env python3
+
+import serial
+import sys
+from datetime import datetime
+
+
+if len(sys.argv) < 3:
+    print("Usage: ./log-serial.py <file_path> <serial_port>")
+    sys.exit(1)
+
+file_path = sys.argv[1]
+serial_port = sys.argv[2]
+
+serport = serial.Serial(baudrate=19200)
+serport.setPort(serial_port)
+serport.open()
+
+# Don't reset the MMC but drive the P2.10 pin to HIGH, so it can be reset
+# externally and execute the application code, not the ROM bootloader
+serport.setRTS(0)  # set RTS line to 3.3V
+serport.setDTR(0)  # set DTR line to 3.3V
+
+
+with open(file_path, "a") as log_file:
+    while True:
+
+        try:
+            message = serport.readline().decode("utf-8", errors="replace").strip()
+            timestamp = datetime.now().strftime("%Y-%m-%d %H:%M:%S.%f %z")
+            log_entry = f"[{timestamp}] {message}\n"
+            log_file.write(log_entry)
+            print(log_entry, flush=True)
+            log_file.flush()  # Always flush when a new log is written
+
+        except serial.SerialException:
+            print("Serial port disconnected. Shutting down...")

scripts/log-serial/log-serial@.service

@@ -0,0 +1,10 @@
+[Unit]
+Description=Serial Logger Service
+
+[Service]
+ExecStart=/usr/local/bin/log-serial.py /var/log/openmmc-serial.log %i
+StandardOutput=journal
+Restart=always
+
+[Install]
+WantedBy=multi-user.target